Abstract
We describe herein the use of Calcium, Barium and Strontium hydroxyapatites (CaHAp, BaHAp and SrHAp) as well as CaHAp containing Magnesium, Copper, Zinc and Palladium (MgHAp, CuHAp, ZnHAp and PdHAp) as catalysts in the Biginelli reaction. The efficiency of CaHAp and SrHAp is very low, leading to the expected 3,4-dihydropyrimidin-2(1H)-one in poor yields. Mixed Ba(5)Sr(5)HAp and BaioHAp show interesting catalytic properties, especially BaioHAp leading to pure isolated reaction products in good yields. The use of modified CaHAp seems to be of interest in regard to the yield obtained. Nevertheless the release of Mg, Cu, Zn and Pd ions in the solution during the catalytic process makes the use of such modified apatites less effective. (C) 2017 Elsevier Ltd. All rights reserved.